OPEC sees no reason for investors to expect oil to hit peak demand before 2040, the organization's secretary general said Monday.

Speaking at the Abu Dhabi International Petroleum Exhibition Conference (ADIPEC), General Mohammed Barkindo said that the cartel's projections did not foresee oil demand cresting over the coming decades.

Instead, he argued, a dramatic increase in global population would likely result in even more people living without access to electricity, cooking gas or heating. "These parameters suggest there will not be peak oil demand before this time (2040)," Barkindo said.

In contrast to OPEC's projections, Shell CEO Ben van Beurden told CNBC in July that he expected demand for oil to peak by the late 2020s or early 2030s in a best-case scenario.

In offering a faster timeline than other closely followed oil market prognosticators, van Beurden said while it was not the oil major's base case scenario, policy and technology developments in the industry could result in peak demand in the medium-term.

Meanwhile, OPEC on Monday forecast higher demand for its oil in 2018 and said its production-cutting deal with rival producers was reducing excess oil in storage, pointing to an even tighter global market next year.

In a monthly report released shortly after Barkindo addressed an energy industry conference, OPEC said the world would need 33.42 million barrels per day (bpd) of OPEC crude next year, up 360,000 bpd from its previous forecast.